*Radiologist Leo Henry Garland (1903–1966) was a pioneer in the study of radiologic error. He conducted rigorous analyses of radiologists’ errors in practice and authored several articles on the topic that were published between 1949 and 1959. Garland discovered that even skilled and experienced radiologists failed to note important findings on 30% of chest radiographs that were positive for disease and also had a false-positive rate of approximately 2% for negative cases.     TITLE: UNDERSTANDING AND CONFRONTING OUR MISTAKES; THE EPIDEMIOLOGY OF ERROR IN RADIOLOGY AND STRATEGY FOR ERROR REDUCTION.  Recent studies confirm similar current results and are identified on our website.

By Paola A. Baron Ródiz, M.D., Radiology Resident at hospital Universitario Severo Ochoa, Leganes, Madrid – Spain and Ferreiro Argüelles, M.D., Neuroradiologist at Hospital Universitario Severo Ochoa in Leganés, Madrid – Spain.

Editor’s Note: The authors of this article received a certificate of merit at ECR 2017 in Vienna for their research.

Around 250,000 people die each year in the US because of medical errors, according to a study by researchers at John Hopkins University School of Medicine. This number is bigger than those who die from car accidents, breast cancers, or work accidents. In fact, medical error constitutes the third leading cause of death in the United States.

Radiologist Leo Henry Garland (1903 – 1966) was the pioneer in the study of radiologic error. The prevalence of radiologists’ errors does not appear to have changed since it was first estimated in 1960. Today, it remains around 10 to 15 percent [1]. Although some diagnoses are missed because of the limitations of the imaging modality, most of them are attributable to image interpretation.

What constitutes an error?

The definition of what constitutes an error in radiologic interpretation is subject to debate.

Some radiological investigations say that the use of the term “error” is often unsuitable. They state that it is more appropriate to use the word “discrepancies” between a report and a retrospective review of a study. Because of the subjectivity of image interpretation, the definition of error depends on an expert opinion. In that order, an observer makes an error if he or she fails to reach the same conclusion that would be reached by a group of experts; and errors can only arise in the cases where the correct interpretation is not in dispute.

Rad errors range from range of 2 to 20 percent

A review made in 2001 reported that the prevalence of clinically significant errors in radiology was in the range of 2 to 20 percent [2]. Approximately 1 billion radiologic imaging examinations are performed worldwide annually and most of the resulting images are interpreted by radiologists. If these interpretations carried an average error rate of only 4% (the lowest estimate for the rate of radiologic error) this would be approximately 40 million radiologist errors per year [1].

In a recent study of second readings performed by experienced abdominal imaging radiologists, they disagreed with each other more than 30% of the time and disagreed with themselves more than 25% of the time [3]. Some studies report that reducing the viewing time to less than 4 seconds increases significantly the miss rate [4].

Mailing address:

1000 W. Valley Rd., # 1343
Southeastern, Pa. 19399

Phone number:


Fax number: 484-913-0238

Please use a cover page and mark confidential.

Email address:

[email protected]